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Sapphire 4850X2 Random Crash

06-08-2009, 10:09 PM

Hi !

This is my first post here, so forgive me if I'm not in line with the local customs...

I recently had to change my mobo on my workstation, and decided to upgrade the GFX card as well (previously, an Nvidia 8600GT was perfectly rocking the box). Considering the price (150?), I bought a Sapphire 4850X2 - but didn't know the ATI linux driver support was so poor (I promised myself 10 years ago never to buy ATI again after some nightmarish driver experience, things didnt change much it seems...)

Well, I suceeded in having Xorg launching (with this card, I HAVE TO enable crossfire, and if I don't, I only get a black screen and a PC lockup). I had to disable compositing as well (it froze the PC)

The problem is, as soon as the card get a bit of stress, either the PC reboot or freeze. There is not enough time for the system to write any log. For example, Google Earth crash the machine after 30 seconds of exploration.

Not to mention the system is perfectly working using any catalyst version under Windows XP.

Comment

Well, in the same price range and where I live, Nvidia speaking, I'll get something like a 250GTS, wich will definetely not please my central 1920x1200 monitor.

Since that 4850X2 has plenty of DVI outputs (4) and some power to give, I think I'll take the challenge... On top of that, IT IS NOT A FAULTY card... It surely need some tweaking, and the drivers are not that great yet (and the Free ones did not even start X), but I'm pretty sure it can run smoothly in linux.

Comment

The callenge for ati is that you are a gamer and not a workstation user, so you lost already. Btw. i checked prices. GTS 250 is available for 105 € on alternate and GTX 260 begins with 145 €, and the GT200 chip should be fast enough for your monitor. So when then compare then use a card from the same price region.

Comment

There have been a variety of posts complaining that power management with the Catalyst driver was less aggressive on Linux than on Windows. If people are saying "my card is drawing more power on Linux" that kind of implies more power would be needed from the power supply, wouldn't it ?

I don't know the current status of Linux vs Windows power draw, but there have been some anecdotal reports of a power difference in the past.

Comment

Last time I checked my PSU was certified by ATI (a Corsair 650W) to work well with this card.

Anyway after digging around, I kinda managed to stabilize the card under 'nux, found out the 9.4 driver just work if I disable cpufreq managment (can't explain exactly why though).

I now have a working setup with compiz functional (though KDE4 compositing effects still freeze the machine, strange I thought they were using the same set of X11 extensions)

Still, while OpenGL work and performances are quite good (one of the few games I play, Future Pinball - DeadHunters via wine, is smoother all maxed & FSAA x4 under linux at 1920x1200 while there is a few stutter under windows).

2D performance though is a bit of a concern.
Movie playback as well, as there seem to be no vsync'ing, and I have to disable compiz to reach some watchable framerate (it used to work ok with compiz enabled on a Geforce 8600GT).

Is there any xorg.conf options to set, so that the card can play movies ok ? Some overlay or acceleration to set up ? The windows driver can play HD flawlessly, so why couldnt the linux do the same ?

Another concern is the heat in the case (wich is quite correclty set up with a rear to front ventilation) : 50/60? (cpu, gpu and mobo as well) when idling seems very high.

Final word, I bought that card partly for the 4 DVI connectors (no other card available with that much ports in this price range), but since Crossfire HAS to be enabled (if not : black screen, SysReq works though), only 2 ports can be used for now with X11.

Bottom line, if anyone passing by and has problem with this card with a >=2.6.29 kernel, use the 9.4 driver, the 9.5 didnt work (maybe 9.6 when it will be out), patched with the 2.9.29 patch, and don't forget to configure both card GPU in xorg.conf, and enable crossfire :